Composition of matter



Patented June 8, 1943 comosmon or MATTER Joy 6. Lichty,Stow, Ohio, assignorto Winfloot,

i UNITED STATES PATENT OFF-ICE Corporation, aware No Drawins.

' 4 Claims.

tion embraces the addition products of amines of aliphatic nature with such zinc salts of dithiocarbamic acids.

Heretofore, zinc salts of certain dithiocarbamic acids have enjoyed wide use as accelerators of the vulcanization of rubber. In the course of investigations to discover improved accelerators of this class, it has been found that addition products of amines, particularly of primary and secondary amines, may be formed with the zinc salts of dithiocarbamic acids, particularly the zinc salts of dialiphatic dithiocarbamic acids. These addition products are, in general, even more powerful accelerators than the zinc dithiocarbamates from which they are derived and are also relatively soluble in petroleum hydrocarbons and in rubber, this property making them particularly valuable in latex compounding.

The zinc dithiocarbamates with which amines may be reacted to give the compounds of the invention may be termed those in which the dithiocarbamate radical contains a secondary or a tertiary nitrogen group, the same resulting from the interaction of a primary or secondary amine and carbon bisulfide, in accordance with the equation a metallic radical or the equivalent being present during the reaction to yield the acid in the form of its salt. R and R1 may represent one organic radical and hydrogen or two individual organic radicals, such as two methyl radicals, or together they may represent one bivalent radical such as pentamethylene or oxy tetramethylene. Usually R and R1 will be aliphatic in nature, including such representative groups as alkyl radicals, alicyclic radicals, aralkyl radicals and the like. The zinc salt of dimethyl dithiocarbamic acid is particularly productive of useful addition products with amines.

Other zinc salts which may be reacted with amines are those of cyclohexyl dithiocarbamic acid, tetrahydro furluryl dithiocarbamic acid, benzyl dithiocarbamic acid, diethyl dithiocarbamic acid, dibutyl dithiocarbamic acid, diamyl dithiocarbamic acid, ethyl cyclohexyl dithiocarbamic acid, dibenzyl dithiocarbamic acid, ditetrahydro furfuryl dithiocarbamic acid, and pentamethylene dithiocarbamic acid.

Still others are the zinc dithiocarbamates derived from di-n-propyl amine, di isopropyl amine, N-methyl cyclohexyl amine, vN-butyl cyclohexyl amine, N-methyl-o-methyl cyclohexyl amine, N- methyl tetrahydro alpha furfuryl amine, N-butyl Akron, Ohio, a corporation of Del! Application May a1, 1940 Serial No. 338,231

This invention relates to a new class of ortetrahydro alpha furiuryl amine, morpholine, sym. diethylethylene diamine, sym. dibutyl trimethylene diamine, N-ethyl-o-methyl cyclohexyl amine, pipecoline, methyl propyl amine, methyl isobutyl amine, 2-ethyl butyl amine and methyl ethyl amine.

The zinc salts of dithiocarbamic acids formed by combination of carbon bisulfide with the following amines may also be used to obtain addition products with additive amines; aliphatic secondary amines, alkyl piperidines, pyrrole, pyrroline, pyrrolidine, di-(2-ethyl butyl) amine, di- (2-ethyl hexyl) amine, alkyl amine, alicyclic betacyano-ethyl amine, dialkoxy propyl amine. and alkyl alkoxy amine.

It will be noted that the foregoing list includes zinc dithiocarbamic acids prepared from both primary and secondary amines, amine addition products being formed with both types of zinc dithiocarbamates.

The amine whichis added to or combined with the zinc dithiocarbamate may be any of the organic amines available, but amines of aliphatic nature are preferred, particularly the alkyl amines, and cyclohexyl amine, piperidine and morpholine have been found to be particularly valuable in the formation of the addition products. Other amines which may be combined with zinc dithiocarbamates to form the compounds of the invention are as follows; primary butyl amine, primary amyl amine, hexadecyl amine, octadecyl amine, dimethyl amine, diethyl amine,

, dibutyl amine, diamyl amine, trimethyl amine,

triamyl amine, ethylene diamine, hexadecyl propylene diamine, dibutyl ethylene diamine, diethylene triamine, and other poly amines, cyclohexyl amine, ethyl cyclohexyl amine, piperidine, furfuryl amine, tetrahydro furfuryl amine, ditetrahydro furfuryl amine, N-butyl tetrahydro furfuryl amine, benzyl amine, mono-o-tolyl ethylene diamine, and di(beta) phenethyl amine.

Other amines which can be combined in the same manner are dipropyl amine, hexahydro ortho or para toluidine, N-methyl cyclohexyl amine, N-methyl" tetrahydro alpha furfuryl amine, N-ethyl tetrahydro alpha furfuryl amine, N-methyl hexahydro o-toluidine, pipecoline, sym. dimethyl ethylene diamine, sym. diethyl trimethylene diamine, sym. dipropyl ethylene diamine, beta phenethyl amine, di(beta phenethyl) amine, heptyl amine, N-methyl isobutyl amine, N-methyl ethyl amine, and N -methyl propyl amine.

To further illustrate the invention, the following examples are given of the preparation or certain addition products.

I EXAMPLE 1 The addition product of cycloheiryl amine and zinc dimethyl dithiocarbamate is prepared by heating to the boiling point a mixture or 0.15

molsof zinc dimethyl dithiocarbamate, 0.495 mols of cyclohexylamine and 200 cc. of water. A colorless solid in an amount of 58.4 grams,

- which is 96% of the theoretical amount calculated for the compound formed by a mol per mol addition product of the amine and zinc dithiocarbamate was obtained. The product melted with decomposition starting at 169 C. Its nitrogen analysis also corresponded to that for the theoretical addition product of cyclohexyl amine with one mol of zinc dimethyl dithiocarbamate.

EXAMPLE 2 In still another example illustrating the invention, 32.7 grams of cyclohexyl amine were added to 47.8 grams of zinc penta methylene dithiocarbamate in 175 cc. of gasoline, the gasoline mixture being stirred meanwhile. The reaction mixture was heated on a hot plate for a short period of time after which the mass was cooled, the solid filtered oil and washed with gasoline. A colorless solid, a mol per mol addition product of cyclohexylamine and zinc penta methylene dithiocarbamate was obtained in an amount of 68.4 grams.

Other illustrative compounds of the invention are those given in the following table:

believed that-such is the case. Also, the melting points or decomposition points, as they may be called, of many of the compounds have in general a fairly wide range. This is probably for the reason that many of the'dithiocarbamates have a melting point above that of the additive amine compound and some decomposition takes place upon the heating incident to obtaining the melting point. It may be that after some 01' the heating, portions of the amine and zinc dithiocarbamate starting materials are present with the addition product. These melting points were conducted in the normal atmospheres.

Several melting points taken in a sealed tube also gave a rather wide range. In the sealed tube the compounds generally started'to melt at a lower temperature, however. Illustrative melting points taken in a sealed tube are as follows:

Table II M. P. in C. Compound Open tube Closed tube Addition product of- Zinc dimethyl dithiocarearbamate+ ditetrahydro iuri'urylamine 190-205 150-195 Zinc dimethyl dithiocarbamete-i- Starts at cyclohexvlamine 169 170-195 Zinc dimethyl dithlocarbamate+dimethylamine 249-250 1 58-220 Zinc dimethyldithiucarbamate-l-benzamine 130-155 127-157 Zinc ethyl cyelohexyl diihiocarbamate +pipcridine -102 80-100 Some of the melting points taken in the open air for the less stable addition products appear to approach the melting point for the zinc dithiocarbamate. For example, the addition product of dimethyl amine and zinc dimethyl dithiocarbamate melted at 249-250 C.,' which is the melting point of zinc dimethyl dithiocarbamate itself.

.Table I Melting or Molecular Zinc salt of dtcic acid derived from Additive amines propor- Product i tlons ion p2 nt in C.

l. Dibutylamine Piperidine 1A; 12 Light tan Solid 05-70 2. Do.. Cyelohexylamine 1A; 12 .do 74-75 3. Do Ethylene diamine 1A; 12 Yellow paste. 4. Do 0 3A; lZ Brown solid 5. Do 1A; 12 Brown semi-soli l.. 6. 1A; 1Z Colorless solid 7. 1A; 12 Ten solid (019 a.

on y 8. Do. Dimethylamine White Solid 249- d as? o Lt. yellow solid 163-170 Lt. cream solid -155 Lt yellow solid 149-151 Colorless solid o 154 Yellow solid. 157-160 Colorless solid. 128-133 .d0.-..-. 244-246 "as 0 14 ....do White solid. 147-149 Cyclohexylamin 1A; 12 .do 155 Tetrahydro alpha iuriurylamlne 1A; 12 Yellow crumbly sol 90-95 Piperidine 1A; 12 Lt. tan Solid- 80-102 1A; lZ do 95-115 1A; 12 Lt. cream solid.. 60-75 1A; 12 ream colored Solid 05-80 1A; 12 Yellow brown liquid 1A;1Z .do

High boiling alkylene poly amines (No. 15) were obtained in the preparation of ethylene diemine, principally diethylene triemine and triethylene tetra amine.

In the third column, "11 refers to the additive amide and Z to the While the molecular proportions have been given, these figures are not known definitely to be the true proportions of the amine and dithiocarbamate in the final products although it is zinc dithiocarbamate.

In each case nitrogen analyses of the compounds were obtained and, where the nitrogen analysis of the product differed from that of the zinc dithiocarbamate, further proved a definite addition 01 the amine to the zinc dithiocarbamate. Typical analyses are as follows:

Zinc dimethyl dithiocarbamatatetrahydroiuriurylamino 8 Table 111 F giifii fihiti fi Zinc dimethyl dithiocarbameteethylene-diamine monohydrate 5 Per can N m 3' m 2 1 3 Found Theoretical values (or c.HuN,s1Zn.3(O1H1N1.H10) Zinc dibenzyl dithioearbamatapiperidine 2:3; $13 3212 1 Found eiariazsaaa 13.3, 13.3 2.1

Per eentN 5. 97, 5.97 6.05 Zine dihutyl dithiocarbamateethylene diamine This application is a continuation in part of mud amazing. m y application Serial No. 44,766, filed October 12,.

1 5. Pel centN 9.92, 9.77 10.5 It will be understood that, while numerous ex- P cents 2L8, amples have been given above, the invention is not limited thereto but includes generally the Zinc dibutyl dithiombamte-emylene amine addition products of zinc dithiocarbamates. Th f Names or Hence, it will be understood that the invention is Found not limited to the compounds described but that various amines may be combined with zinc salts P N m8 mg 17.2 of various dithiocarbamic acids, without depart- PZ: 223i: sIIIIIII 19.6. 19.0 19.6 25 ing from the spirit of the invention or from the P cent Z11 10-4, scope of the appended claims. Similarly, while various theories have been put forth herein, it Zinc dlbuwl dithiwbemm-amyl will be understood that the invention is not to be limited thereby. It is intended, then, that the Found patent shall cover, by suitable expression in the appended claims, all features of patentable nov 7 50 elty residing in such invention. no What I claim is: 1. The addition products of a cyclohexylamine compound selected from the class consisting of Zinc dimethyl dithiocarbamatenyclohexylamine mme, N-ethyl cyclohexylamine and N-methyl cyclohexylamine and a zinc salt of a Found ggggfgflggfg f flflg dialkyl dithiocarbamate.

2. The additional products of cyclohexyl amine Per mm 9 53 9 46 1M 40 and a zinc salt or a dialkyl dithiocarbamic acid. 3. The addition product of cyclohexyl amine Zine dlmethyl dithiocarabamatadibutyl ethylene diamine ggfig l lgggg-g gi gy cyclo- Themflml 1mm, hexylamine and zinc dimethyl dithiocarbamate. Fmmd CQHNQSZILOHHMNI I JOY G. LICH'I'Y. Per eentN 11.1, 11.0 11.7

CORRECTION OF CORRECTION. Patent No. 2,521,501. June 8. 9

JOY G. LICHTY.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, second column, line 15, for "alkyl amine" read--a1kyl beta-cyanoethyl amine-; p g 5, first column, line 1- Table for "dithiocarabamate" read--d'ithiocarbamate; and second column, line 59, for "additional" read "addition-; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 15th day of July, 19h

Henry Van Arsdale, Acting Commissioner of Patents. 

